Driving with the windows down vs the air con on

Driving with the windows down vs the air con on

I am not sure what do you guys practice, but whenever I have the opportunity to drive (at night), I prefer to do so with the windows down, all four of them to around three-quarter levels, and enjoy the wind as I travel in the highway or partially filled roads.

Although it isn’t similar to the wind in your hair experience that one experiences in a convertible, it’s the closest I can get, and the reason I can only do it at night is because it is cooler, and I won't be breathing in harmful emissions at traffic lights.

Besides pleasure and preference, there is a popular belief that driving with the windows down saves more fuel than having the air conditioner turned on with the windows up.

And in contrast, there is an alternate theory that suggests driving with the windows down increases drag, or air resistance around the car, and thus ends up sipping more fuel - because to resist this motion - the car needs more power, which in turn, burns more fuel.

So which is which?

While it is true that utilising air-conditioners while driving does in fact contribute to a higher fuel usage, a study from a U.S. based Society of Automotive Engineers (SAE) have apparently found the opposite. It is more fuel efficient to drive with the windows up and the AC on.

The test also claimed a 20 percent reduction in mileage when the windows were rolled down whereas with the AC on, fuel efficiency dropped by just 10 percent.

The test results can be altered by a number of factors, including the type of car (an SUV experiences higher drag than a small car), aerodynamic properties of the vehicle, outside temperature, wind speed, etc.

In general, it is recommended to drive with the windows down at speeds below 70km/h - as the power unit develops less power and it has to work harder to operate the AC and other components that rely on power from the motor. Besides, as you are driving slowly, the drag resistance is not strong enough to cause any significant damage to fuel efficiency.

However, given our tropical conditions, I suggest we practice this recommendation, in the evening or wee hours of the morning when the air is cooler and there are less cars on the road.

When driving at higher speeds, you might want to roll up the windows and have the AC turned on, as the engine produces enough power to run the AC along with resisting the higher drag property that comes with speed.

But then again the faster you go with the windows rolled down, the more forceful air gets gushed in and thus a more lively experience? At the end of the day, it all comes down to personal preference and several trials and errors.

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mmm....guess it's not much of fuel efficiency...its about overall performance diverting it away from ac. very obvious performance improve when ac are off and running on manual gear but not much on automatic gear as they have lag time before switching to the next gear. in result of longer drag time.

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With the end of the Circuit Breaker measures, more people have resumed working, creating more traffic on our roads.
But that has not stop this rider from riding recklessly on his Personal Mobility Device (PMD) in Sembawang.
As reported by SG Road Vigilante, the rider can be seen overtaking a car that is moving away from the traffic lights before keeping up to speed with it.
In fact, the video which was shot on the 4th of June, showed the rider overtaking a motorcycle in the next lane.
Judging from the 20 seconds plus clip, we reckon he could have been doing twice the legal speed limit of PMDs (25km/h).
Naturally, netizens were quick to slam him...
Should we be tolerating this? Watch the video of the PMD rider here!
101385818_2673239402892083_8980883442018037830_n.mp4

Now that is one close shave.
As seen on SG Road Vigilante's facebook page, an Audi TT failed to stop at the give way line, nearly crashing into a Mitsubishi Lancer Ex which had the right of way on 29th of April
Eagle-eyed readers would have definitely spotted the P-plate sign on the Audi, signaling to us that this might just be a rookie's honest mistake.
In our opinion, we thought the camera car would have gotten a larger shock, seeing the Lancer swerve into his lane along Sengkang West Road.
On another note, should the Lancer have slowed down instead of (recklessly)accelerating into the camera car's lane?
Let us know in the comments below!
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Our Circuit Breaker measures sure bring up quite a few weird incidents. I mean why would you even cycle in an expressway tunnel?
As seen on ROAD.sg's website, it did seemed like someone cycled along our Marina Coastal Expressway on the 9th of April and was stopped by a Special Operation Command Police vehicle.
As uncommon as it is to see a cyclist on an expressway, it is even rarer to see someone from the SOC stop a traffic offender as it is not part of their job scope.
Kudos to the fellas for going the extra mile!
Even netizens on the facebook page were also grateful to police force!
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Could this be another case of street racing spotted on our roads during the Circuit Breaker period?
Spotted on Reckless Driver SG's facebook page, a video has been posted showing the camera car driving slowly on the middle land before a small group of cars went past it at a higher speed.
Yes. this is milder than the incident on the KPE that had the drivers in the video arrested, with only three cars shown in the short 40-plus-second clip. In fact, we reckon the 'tiong chias' were doing approximately 120-140km/h while the camera car was doing 70-80km/h.
The cars, likely a Ford Focus, a Honda FD Civic and a Honda Integra were caught on camera at around 11:20pm on the 25th of May heading towards AYE Jurong inside the CTE tunnel.
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On another note, we were surprised to find most of the comments attacking the video owner, saying that the camera car was road-hogging.
Do you agree? Let us know!